Automatic shutoff device



Jan. 13, 1953 1'. E. PARRISH I AUTOMATIC SHUTOFF DEVICE Filed Oct. 12.1950 ATTORNEY FIG. 2.

Patented Jan. 13, 1953 UNITED STATES PATENT oFFIcE,

Tom E. Parrish, Beaumont, Tex.

Application October 12, 1950, Serial No. 189,743

The invention concerns an automatic shutofi device for use in connectionwith a battery of one or more tanks such as those commonly used in oilpipe line gathering systems. It is common practice to pump oil from twoor more of such tanks at the same time, the draw-ofi lines from theseveral tanks being served by a common pipe line. Ordinarily the liquidlevel in the several tanks of the battery becomes equalized duringpumping. A pipe line may be fed by a number of such batteries of tanks,taking suction on allof them at the same time. The shutoff device of theinvention may be used to shut off the flow of liquid from a given tankor battery when the liquid level therein has dropped below a certainpoint, such, for example, as the point where the draw-off line entersthe tank. At the same time the connection between the draw-off line andthe pipe line is positively closed so that no air is admitted to thepipe line from the tank. The present application constituting acontinuation in part of my prior co-pending application filed December'7, 1946, and bearing Serial No. 714,819, now Patent No. 2,570,372.

A number of devices intended to be used for the purpose described arenow on the market, and others are disclosed in previously issuedpatents, but none of them are entirely satisfactory.

In my earlier patent, No. 2,489,461, dated November 29, 1949, I havedescribed and claimed an automatic shutofi device for liquid conductinglines. The automatic shut-off device described in this application is animprovement over the one described in the patent referred to. It is anobject of the invention to provide an automatic shutofi device which isadapted to shut ofi the flow of liquid from a tank withoutpermitting'air to enter the pipe line from the tank. The presence of airin a pipe line destroys the suctionand thus interfereswith the pumpingoperation.

It is also an' object of the invention to provide a float controlledshutofi valve which is fully automatic and is so designed that the floatwill'ris'e "and fall freely in response to fluctuationsin liquid leveland the valve willbe properly seated." I q Another object of theinventionis to provide, in conjunction with an automatic shutoff deviceof the type described, means for preventing the flow of liquid inreverse direction from the shutoiT device to the tank. v Such anarrangement is desirable in order to prevent possible overflow of thetank by the flow of liquid thereto from another tank positioned at ahigher elevation or havingahigher liquid level.

3 Claims. (01. 137-174) A further object of the invention is to providea float controlled shutoff valve in which the flow of liquid from thetank to the float chamber is utilized to lift the valve from its seat,thereby breaking thevacuum in the discharge line and permitting thefloat to rise and fall freely.

A further object of the invention is the method of controlling the levelof liquid fluid in the tank or receptacle flowing through a shutofidevice ofthe character described into a pipe line system. The inventionwill be readily understood by refterring to the fOllOWiIlg descriptionand the accompan'ying drawing, in which:

' Fig. 1 is a diagrammatic view in elevation showing one of a. batteryof tanks having its drawoff line connected to a header which may beconnected also to other tanks of the battery (not shown), with theautomatic shutoff device of the invention interposed between the headerand the 'pipe line.

Fig. 2 is a sectional view in elevation of the shutoff device, showingthe valve in closed position.

Fig. 3 is a sectional view taken on the line 3-3 of Fig. 2.

Fig. 4 is a sectional view taken on the line 4-4 of Fig. 2.

Referring to the drawing, the numeral l indicates a tank which isconnected thru valved draw-off line 2 to a header 3. The tank I issituated above the ground, while the header 3 is buried below thesurface. A riser 4 connects the header 3 with the shutofi device of theinvention, which is indicated generally by the numeral 5. The shutoffdevice 5 is connected by a discharge pipe 6 to a pipe line (not shown).

The shutofi device 5 comprises a vertically disposed cylindrical casing1 which is of relatively "large diameter and provides a float chamber ofconsiderable cross sectional area. An inlet pipe 8 and'an outlet pipe 9enter the casing I from the bottom and extend upwardly a short distancetherefrom.

A cylindrical float' l -0 isreceived bodily within the-casing I. 'Thediameter of the float l0 isonly slightly-less than the inside diameterof the casing 1. A pair of longitudinal openings II and 12' are formedin the body of the float III, on opposite sides thereof, for use asguides as hereinafter described.

, Valve discs l3 and I4 are provided for closing the upper end of theinlet pipe 8 and the outlet pipe 9. The valve discs l3 and I4 are madeof a tough; resilient, rubber-like material such as neoprene, reenforcedon each side with metal. The upper end of the outlet pipe 9 is slightlyhigher than that of the inlet pipe 8. Metal rings and I6, which may bemade of Monel or other suitable metal, are attached to the upper ends ofthe inlet pipe 8 and the outlet pipe 9 and function as valve seats.

The upper end of the inlet pipe 8 is surrounded by a cylindrical valvecage I], the valve cage I! being open at the top and being attached atits lower end to the bottom of the casing I. A plurality of ports [8 areformed in the wall of the valve cage ll. A plurality of verticallydisposed, wire-like guide members [9, whichare attached at their lowerends to the valve disc l3 and at their upper ends to a wire-like ring29, are receivable within the valve cage 11 and spaced about the wallthereof.

A pair of vertically disposed, tubular guides 2| and 22, each of whichis movable longitudinally :as hereinafter described, are aligned withthe center lines of the inlet pipe 8 and'the outlet pipe 9. The tubularguides 2! and 22 are inserted thru the openings I l and 12 formed in thebody of'the float l0 and serve to maintain the float 1:0 in verticalalignment.

The upper end of the casing I is closed by a cover-plate 23. A pair ofvertically disposedguide rods 24 and 25, which slidably engage the upperends of the tubular guides 2i and 22, are suspended from the cover plate23 as hereinafter described. Theguide .rod 24 extends thru an openingformed in the cover plate 23 and a nut '25 is secured to the upper endthereof, above the cover plate 23. The guide rod 25 extends thru anopening formed in the cover plate 23, and the upper end thereof issecured to one end of a lever 2.7 which is mounted on the cover plate23. A shoulder 23 is formed on the lower end of the guide rod 25 and isadapted to engage an internal shoulder 29 formed near the upper end ofthe tubular guide 22 whereby the tubular guide 22 may be lifted uponmanipulating the 1ever'21. The lower end of the tubular guide 22 isconnected, thru .a ball joint 39, to the valve disc [4 whereby the valvedisc 14 may be lifted from its seat by the action of the lever 21 on'theguide rod 25 and the tubular guide 22. This arrangement is particularlyuseful when it is desired to drain the tank completely preparatory tocleaning.

The lower end of the tubular guide 2| rests freely upon the uppersurface of the valve disc [3 when the valve disc I3 is seated. Ashoulder 3| is formed on the tubular guide 21, below the float Ill, andis adapted to engage the float .19 to lift Y it when the valve disc I3is lifted from-its seat by the action of liquid flowing thru the inletpipe 8. A shoulder 32 is formed on the tubular guide. "22, above thefloat l0, and is adapted to be engaged by the float l0 whereby thetubular guide :22 is raised, and the valve disc I 4 is lifted from itsseat, as the float H3 is raised by the action of the valve disc l3 onthetubular'guide 2|. A shoulder 33 is formed on the tubular guide 2|, abovethe. float 119, and is adapted to. be engaged by the float {8 wherebythe tubular-guide 2;! may be lifted out :oi the casing 1 along with :thefloat l0 upon dismantling the apparatus.

A hollow valve body 35 is connected to the lower end of a tubularsection 42 which is attached to the cover plate or flange 23 at the top.of the casing I. The valve body 35 having a beveled annular valve seat43 interiorly thereof with an opening therethrough in communication withthe opening in said tubular section 42. A valve stem 36 is slidablyengaged through the lower portion of said valve body 35 and the lowerportion of said valve stem 36 is connected to a float 31. The upperportion of the valve stem 36 is formed into a conical shaped valve head44 adapted to seat in beveled annular valve seat 43 and to work withinlimits of seated and unseated position. A plurality of ports 45 throughthe side walls of said valve body 35 in communication with the interiorof the casing i and the interior of said valve body '35. A hollow checkvalve body 38 is attached to the upper end of tubular section 42 withopenings therethrough in register with the opening through said tubularsection 42.

A plate valve 43 is made of rubber or other suitable material and ismovable freely within limits interiorly of said hollow check valve body38 between an upper valve seat 41 and a lower valve seat 48 formedinteriorly of said hollow check valve body 38 and being of suchdimensions to close the vertical openings through said upper and .lowervalve seats and yet be a loose slidin fit interiorly of said hollowcheck valve body 38 so as to worlrfreely therein. A plurality of lateralports 49-49 are formed above the upper valve seat :47, which ports arein communication with the vertical opening through said upper valve seat4'! and the interior of said hollow check valve body 38. A stopcockvalve of usual construction is attached to the top of the check valvebody 38 which has openings therethrough and is provided for emergencyuse only, and normally ,remains in open position. vA vent pipe 34 isattached to the top of said stopcock valve 3.9 and is provided withscreen 50 which is held in place by cage 5! to prevent insects anddebris from stopping up the exit of the vent pipe 34. The diam- .eter ofsaid plate valve 46 issuch that air and/or .gasmay by-pass said valve toenter ports 49-49, thence through stopcock valve 39 and thence throughvent pipe 34 thereabove to the atmosphere when the air and/or gas fluidis bein vented out of said casing I, however, the plate valve 46 willprevent air from the atmosphere to enter said casing 7 when seated onvalve seat 48 which occurs when the float controlled valve 44 seats onseat 43 in response to the liquid fluid present in the casing duringnormal operations of the shutofi device.

A gauge rod 49 is slidably suspended from the cover plate 23 whereby itis movable longitudinally. The lower end of the gauge rod 40 is engaged'by the float ID as the liquid level in the casing 19 rises, and theposition of the float l0 may be determined by observing the position ofthe gauge rod 49,. The. upper end of the gauge rod 40 is enclosed in asight glass 4! The operation .of the automatic shutoif device of-theinvention is as follows:

With the tank I full of liquid and with :the valved draw-off line 2closed, and assuming that no liquid is flowing thru the header 3 fromother tanks of the battery (not shown), the discharge pipe 6 will besealed off from the shutoff device 5 :by seating of the valve disc 14 on.the valve seat I 6 in the outlet pipe 9. Upon opening the valveddraw-off line 2, liquid begins to flow thru the header 3 and the riser4, and enters the casing 1' thru the inlet pipe 8. The valve disc I4tends to remain seated due to the vacuum created by liquid moving thruthe pipe line (not shown), but this tendency is at least partiallyovercome by the buoyancy of the float In, which tends to lift the valvedisc 14 from the valve seat I6. Moreover, the liquid entering the casing1 thru the inlet pipe 8 acts upon the under side of the valve disc Hi tolift it from the valve seat l5. As the valve disc 13 is lifted fromthevalve seat l it abuts the lower end of the tubular guide 2|, lifting italso, and the shoulder 3| on the tubular guide 2| contacts the float IDin its ascent forcing the float H] to contact the shoulder 32 on tubularguide 22 which forces the tubular guide 22 to lift the valve disc M fromthe valve seat l6, thereby breaking the vacuum which tends to maintainthe valve disc [4 firmly seated. Thereafter the float Ill rises freelyas the level of liquid in the casing 1 increases, and liquid is causedto fiow thru the outlet pipe 9, the discharge pipe 6 and the pipe line(not shown). As the level of liquid in the casin I rises the float Illrises therewith contacting float 31 to force the valve head 44 to seatin the valve seat 43 to seal oiT the vent, thereby stopping the flow ofair or other gas from the casing 1 thru the vent pipe 34. In event ofmechanical difficulty and float l0 does not rise with the enteringliquid in the casing I, then as the liquid level rises and contactsfloat 3'! the float 31 will ascend with the liquid and force the valvehead 44 to closed sealed-off position in the valve seat 43 thus theabove construction provides a double safety factor insuring positiveshutofi of the vent to prevent the oil or other liquid fluid from beinglost through the vent. In the meantime a portion of the air or other gaswill a have been exhausted from the casing 1 by the rising level ofliquid therein through the ports 45.

' hollow valve body 35, thence through tubular section 42, thencethrough check'valve body 38 bypassing plate valve 46, thencethroughsmall latbeen observed, by use of level gauges, that the float Illordinarily will not at any time be more than slightly immersed in theliquid flowing thru the casing 1. Thus the liquid in the casing I doesnot tend to be exhausted thru the vent pipe 34.

The valve head 44 normally remains seated while liquid is flowing thruthe casing 1, thus preventing the passage of air or other gas to or fromthe casing 1 thru the vent pipe 34. On the other hand air or other gasmay enter the casin I from the pipe line (not shown), thru the outletpipe 9. This will increase the volume of air in the upper portion of thecasing I and the liquid level will be forced downwardly and the float l0and float 31 will be caused to lower slightly, thus unseating the valve44 proportionately until a suflicient amount of air and/or gas is ventedto the atmosphere whereupon the liquid level in the casing I rises againto automatically raise the floats l0 and 3'! which react to close thevalve 44. This permits air or other gas at stated intervals to beevacuated-from the pipe line (not shown), which is desirable. Air orother gas will be exhausted from the casing 1 thru the vent pipe 34until the pressure of the compressed air or other gas in the upperportion of the casing I is again balanced against the pressure createdby the static head of liquid in the tank I.

As the liquid level in the tank I approaches the liquid level in thecasing l, the compressed air above the float approaches atmosphericpressure.

direction from the casing 1 to the tank I.

' As the liquid level in the'tank I continues to lowf er, a vacuum formsabove the liquid level in the casing 1 and tends to hold'the' liquidat ahigher level than the liquid level in-the tank I. Finally, as the liquidlevel in the tank I approaches the top of the draw-off line, a smallamount of air enters the draw-off line and the casing 1 from the tank I,breaking the vacuum above the liquid level in' the casing l, and causesthe valve l4 to be seated quickly.

The valve disc i3 is adapted to close the inlet pipe 8 and to preventthe flow of liquid in reverse This arrangement prevents overflow of thetank I due to the flow of liquid to the tank I from another tank towhich it may be connected, and eliminates the expense of a seperatecheck valve for this purpose. Thus when pumping simultaneously fromtanks positioned at diiTerent elevations, or having different liquidlevels, the tank positioned at the highest elevation, or having thehighest liquid level, automatically is pumped out of before tanks havinglower liquid levels or positioned at lower elevations, the'levels in theseveral tanks eventually being equalized. v

The invention maybe modified in various ways without departing from thespiritand scope thereof. I

I claim:

- 1;- An automatic shut-off device for fluid conducting lines comprisinga vertically disposed cylindrical casing,- an inlet pipe and an outletpipe connected to 'the'bottom of thecasing-and extending upwardly ashort distancetherefrom, valve seatsin the upper ends of the inletpipeand the outlet pipe, valve discs adapted to be seated on the valveseats, a cylindrical valve cage surrounding the upper end of the inletpipe and attached at its lower end to the bottom of the casing, thevalve oage being open at the top and a plurality-of ports being formedin the wall thereof, a valve guide received within the valve cage andattached to the adjacent valve disc, a cylindrical float received bodilywithin the casing,

"a pair-of longitudinal openings being formed in -the body of the floaton opposite sides thereofia pair of vertically disposed tubular guidesaligned -with the center lines of the inlet pipe and the outlet pipe,the tubular guides being movable longitudinally and being looselyinserted thru the openings in the body of the float, the lower end ofone of the tubular guides resting freely upon the upper surface of thevalve disc in the inlet pipe when the valve disc is seated, the lowerend of the other tubular guide being connected thru a ball joint to thevalve disc in the outlet pipe, a guide rod rigidly secured at its upperend to the top of the casing and slidably engaging the upper end of thefirst mentioned tubular guide, a second guide rod slidably engaging theupper end of the last mentioned tubular guide and suspended from the topof the casing, a shoulder being formed on the first mentioned tubularguide below-the float and a shoulder being formed on the last mentionedtubular guide above the float, a vent pipe extending thru the top of thecesing, and a float operated valve in the vent p p 2. An automaticshutofl device for fluid conducting lines comprising a verticallydisposed cylindrical casing, an inlet pipe and an outlet pipe connectedto the bottom of the casing and extending upwardly a short distancetherefrom, valve seats in the upper ends of theinlet pipe '7 and theoutlet pipe, valve discs. adapted to be seated on the valveseats, acylindrical valve, cage surrounding the upper end of the inlet pipe andattached at its lower end to the bottom of the casing, the valve cagebeing open at the top and "a plurality of ports being formed in the wallthereof, a valve guide received within the valve :cage and attached tothe adjacent valv disc, a cylindrical fioat received bodily within thecasing, a pair of longitudinal openings being formed in the body of thefloat on opposite sides thereof, a pair of vertically disposed tubularguides aligned with the center lines of the inlet pipe and the outletpipe, the tubular guides being movable longitudinally and being looselyinserted thru the openings in the body of the float, the lower end ofone of the tubular guides resting freely upon the. upper surface of thevalve disc in the inlet pipe when the valve disc is seated, the lowerend oi the other tubular guide being connected thru a ball joint to thevalve disc in the outlet pipe, a guide rod rigidly secured at its upperend to the top of the casing and slidably engaging the upper end of thefirst mentioned tubular guide, a second guide rod slidably engaging theupper end of the last mentioned tubular guide and suspended .from thetop of the casing, a shoulder being formed on the first mentionedtubular guide below the float and a shoulder being formed on the lastmentioned tubular guide above the float, a vent pipe extending thru thetop of the casing, a valve housing connected to the vent pipe, a valveseat and .a valve in the valve. hous .ing, a valve stem connected at itsupper end to thevalve, and a float connected to the lower end of thevalve-stem.

3. An automatic shutofi device for fluid conducting lines comprising avertically disposed cylindrical casing, an inlet pipe and an outlet pipeconnected to the bottom of the casing and extending upwardly a shortdistance therefrom,

- valve, seats in the upper ends of the inlet pipe and the outlet.pi-pe, valve discs adapted to be Y seated on the valve seats, acylindrical valve cage surrounding the-upper end of the inlet pipe andattached at lower end to the bottom of the casing the valve cagebeingopen at the top and a plurality of ports being formed in the wallthereof, a valve guide receivedwi-thin the valve cage and attached tothe adjacent valve disc,

8 a cylindrical 'fioat received bodily within the casing, a pair oflongitudinal openings being formed in the body of. the float on oppositesides thereof, a pair of vertically disposed tubular guides aligned withthe center lines of the inlet pipe and the outlet pipe, the tubularguides being movable longitudinally and being loosely inserted thru theopenings in the body of the float, the lower end of one of the tubularguides resting freely upon the upper surface of the valve disc in theinlet pipe when the valve disc is seated, the lower end of the othertubular guide being connected thru a ball joint to the valve disc in theoutlet pipe, a guide rod rigidly secured at its upper end to the top ofthe casing and slidablv;

tubular guide, a second guide rod slidably en'- gaging the upper end ofthe last mentioned tubular guide and extending thru an opening in thetop of the casing, a shoulder being formed on the lower end of thesecond guide rod and an internal shoulder being formed on the lower endof the last mentioned tubular guide, the upper end of the second guiderod being secured to one end of a lever mounted on the top of thecasing, a shoulder being formed on the first mentioned tubular guidebelow the float and a shoulder being formed on the last mentionedtubular guide above the float, a vent pipe extending thru the top of thecasing, a valve housing connected to the vent pipe, a valve seat and avalve in the valve housing, a valve stem connected at its upperend tothe valve, and a float connected to the lower end of the valve stem.

TOM E. PARRISH.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS

